<template>
    <div class="nav-bar" :class="{'is_fixed':isFixed}">
        <div class="container"  >
            <div class="pro-title">
              {{title}}
            </div>
            <div class="pro-param" >
                <a href="javascript:;">概述</a><span>|</span>
                <a href="javascript:;">参数</a><span>|</span>
                <a href="javascript:;">用户评价</a>
                <slot name="buy"></slot>
            </div>
        </div>
    </div>
</template>
<script>
export default {
    name:'nav-bar',
    props:{title:String},
    data() {
        return {
            isFixed:false
        }
    },
    mounted() {
        window.addEventListener('scroll',this.initHeight)
    },
    methods: {
        initHeight(){
            let scrollTop = window.pageYOffset || document.documentElement.scrollTop || document.body.scrollTop

          this.isFixed = scrollTop>152? true : false;
        },
        destroyed() {
            window.removeEventListener('scroll',this.initHeight,false)
        },
    },
}
</script>
<style lang="scss">
@import "../assets/scss/mixin.scss";
@import "../assets/scss/config.scss"; 
    .nav-bar{
        height: 70px;
        line-height: 70px;
        border-top: 1px solid $colorH;
        background-color: $colorG;
        z-index: 10;
         &.is_fixed{
                 position: fixed;
                 top: 0;
                 width: 100%;
                 box-shadow: 0 5px 5px #cccccc;
              }
        .container{
            @include flex();
         
            .pro-title{
                font-size: $fontH;
                color: $colorB;
                font-weight: bold
            }
            .pro-param{
                font-size: $fontJ;
                span{
                    margin: 0 10px;
                }
                a{
                    color: $colorC;
                }
               
                
            }
            
          
        }
         .aa{
                height: 350px;
            }
         
    }
</style>
